DE application 10222192 describes pentafluorosulfanylbenzoylguanidines as NHE1 inhibitors. The processes described therein for preparing these compounds, however, result in low yield and require reagents and reaction conditions that necessitate great technical complexity or are unsuitable for preparation on a relatively large scale. It has now been found that said disadvantages can be avoided by a novel efficient synthesis which starts from commercially available 4-nitrophenylsulfur pentafluoride.